A two year project to repeat a famous bird survey by driving over 20, 000km in a 4x4 across Botswana has confirmed researchers' fears: many birds of prey are fast disappearing from one of Africa's last great wilderness areas. Reported sightings of iconic species of eagle and vulture declined by as much as 80% compared with the previous survey, while some migrant species recorded last time have vanished, according to the study published this week in the international scientific journal Biological Conservation.
The data is based on a return trip to a network of roads criss-crossing most of Northern Botswana, an area first surveyed over twenty years ago by a former Wildlife Biologist with the Department of Wildlife and National Parks Botswana, Dr. Marc Herremans.The resurvey focussed on 29 raptor species and compared their encounter rate with Herremans's original records.
"The main motivation for doing the work was to explore whether vultures and other raptor numbers had declined in Botswana like they have in many other areas of Africa" says Associate Professor Arjun Amar from the Fitzpatrick Institute of African Ornithology at the University of Cape Town which conducted the study in collaboration with conservation NGO Raptors Botswana.
Some of the species showing the greatest declines are the White-headed vulture (Trigonoceps occipitalis) and Lappet Faced vultures (Torgos tracheliotos), African Hawk Eagle (Aquila spilogaster), Secretary Bird (Sagittarius serpentarius), Bateleur Eagle (Terathopius ecaudatus), and Red-necked Falcon (Falco chicquera).
Source: Phys Org, June 6, 2018